lib/PublicInbox/LeiMirror.pm | 2 +-

diff --git a/lib/PublicInbox/LeiMirror.pm b/lib/PublicInbox/LeiMirror.pm
index 4464b6b109b9bc1884c6a3d1a8cd73d29980927f..8b276336f288258a4a45a385ee37ee325802b384 100644
--- a/lib/PublicInbox/LeiMirror.pm
+++ b/lib/PublicInbox/LeiMirror.pm
@@ -602,7 +602,7 @@ 	my $cerr = $?;
 	$? = 0; # don't let it influence normal exit
 	if ($cerr) {
 		kill('TERM', keys %$LIVE);
-		$self->{lei}->child_error($cerr, "@$cmd failed");
+		$self->{lei}->child_error($cerr, "@$cmd failed (\$?=$cerr)");
 	}
 }